NAT keepalive is a feature that sends very tiny data packets, called UDP packets, from a VoIP phone to the router to show that the port is still in use. The phone will send these small packets at timed intervals set by your phone or your phone system.

msdn.microsoft.com May 20, 2014 · There is a feature in Remote Desktop Services that when enabled, sends a keep-alive packet from the server to the client at a specified interval. If the client responds, the server keeps the client status as active, and the traffic created by the keep-alive packets themselves resets the idle timer within the load balancer. tcpIpApp.keepalive.tcp.noResponseTransmitInterval . Specifies the amount of idle time between the transmission of the keep-alive packets the TCP stack waits on VVX phones and the SoundStructure VoIP interface. This applies whether or not the last keep-alive was acknowledged. TCP Keep-Alive - Occurs when the sequence number is equal to the last byte of data in the previous packet. Used to elicit an ACK from the receiver. TCP Keep-Alive ACK - Self-explanatory. ACK packet sent in response to a "keep-alive" packet. TCP DupACK - Occurs when the same ACK number is seen AND it is lower than the last byte of data sent by

HTTP keep-alive (also known as persistent connections) is keeping the TCP socket open so that another request can be made without setting up a new connection. TCP keep-alive is a periodic check to make sure that the connection is still up and functioning.

Apr 24, 2019 · Keepalive. Use. This command changes how often an interface sends a keepalive to prove to its directly connected neighbor it is still up/up. The default is 10 seconds. Syntax. Router(config-if)#keepalive Example. In this example, we will lower Fa0/0’s keepalive to 5 seconds . Hi, We have started using the TCP keep alive mechanism. Things are ok when the firewall is down. When the firewall is active, the TCP keep alive packets are dropped by the firewall. How can I configure the firewall to let the packets through? The TCP ports change with each session so I can't

SMB2/KeepAlive. Opcode 0x0d . This SMB2 command can be used to "ping" that the other end is still alive. It can even be used prior to the SMB2/SessionSetup command. SMB2/KeepAlive Request. SMB2/KeepAlive Request Packet Format

The broker must disconnect a client that does not send a a message or a PINGREQ packet in one and a half times the keep alive interval. Likewise, the client is expected to close the connection if it does not receive a response from the broker in a reasonable amount of time. Keep Alive Flow. Let’s take a closer look at the keep alive messages.